1. Field of the Invention
This invention relates to gas insulated substation equipment and more particularly to "Y"-shaped enclosure elements providing a modular approach to gas insulated substation manufacturing and usage.
2. Description of the Prior Art
In recent years, there has come about a demand for a reduced-size substation. This demand on the part of public utilities has been met by gas insulated substation equipment. This type of substation equipment significantly reduces the space required by the high voltage value of substations rated for example, 46 KV through 500 KV. Space reduction is accomplished by replacing the open-bus and the air-tight bushings with a gas insulated bus filled, for example, with a highly insulating gas such as sulphur hexafluoride gas at a pressure, for example, of 45 pounds per square inch gauge and thereby permitting the movement of electrical equipment very closely together.
This gas insulated substation equipment has many advantages, among which are: significant reduction in size requirements both in land area and overall height; added system reliability by eliminating the possibility of phase-to-phase faults, lightening strikes within the system, or contamination of insulators; reduced maintenance because the closed system is isolated from the environment; added personnel safety because all live parts are covered by ground shields; and lower installation costs as compared with conventional or other types of power systems when the gas insulated compartment approach is utilized.
The gas insulating system, as briefly described above, has additional design advantages, inasmuch as the high voltage equipment is compressed, so that both the space required and the total length is minimized. The power transformers may be located on outside corners so as to be capable of ready removal, and the location of cable pot heads is flexible, with results that the system may be readily connected to overhead transmission lines.
However, the costs of manufacturing such gas insulated components are very expensive. Additionally when circuit control device mechanisms such as circuit breakers, ground switches and disconnect switches are utilized, each piece of equipment requires individualistic enclosure elements. This therefore reduces the mass production potential thereby keeping manufacturing costs higher than is desirable.
The use of singular "Y"-type gas insulated substation equipment is taught in various patents. In U.S. Pat. No. 4,223,191 "Upstanding Mounting Structure For High-Voltage Three-Break Live-Module Circuit-Breaker" issued Sept. 16, 1980 to Calvino assigned to the assignee of the present invention, there is illustrated a "V"-shaped supporting structure with an interconnecting support structure thereby looking like an inverted "A"-structure. Additional "Y"-type structures are taught in U.S. Pat. No. 4,131,775 "Compressed-Gas Circuit-Interrupters Of The Puffer-Type Having Improved Supporting, Shielding And Assembly Features", issued Dec. 26, 1978 to Meyer et al.; U.S. Pat. No. 3,935,408 "Heating Means For High-Voltage Gas-Type Circuit Interrupter" issued Jan. 27, 1976 to Taylor, U.S. Pat. No. 3,846,601 "Compressed-Gas Circuit Interrupter" issued Nov. 5, 1974 to Leeds; U.S. Pat. No. 3,662,128 "Readily Transportable Circuit Breaker Of Two-Piece Segmented Frame Construction And Two-Positioned Operating Mechanism Housing" issued May 9, 1972 to Neudorfer et al.; all assigned to the assignee of the present invention. Additionally, U.S. Pat. No. 4,019,007 "Grounded-Tank High-Power Compressed-Gas Circuit-Interrupter" issued Apr. 19, 1977 to Friedrich et al. and assigned to the assignee of the present invention teaches a modified "H"-type circuit protection structure.
The above patents while teaching various methods of modular construction, still require a specific structure for a specific circuit control device. Therefore a circuit breaker mechanism would have a structure which was designed for the circuit breaker mechanism alone and therefore a ground switch mechanism, as an example, would not be properly suited. Additionally, the above structures are not modular to the extent that they are not serially connectable with identical elements. They therefore do not allow differing control devices to be serially connected, such as a circuit breaker, a disconnect switch, and a ground switch or any combination thereof without requiring separate and distinct structures for each mechanism.
There was a limited disclosure of the subject matter of the present application on or about Dec. 5, 1977 to the U.S. Department of Energy in an oral and related presentation by the assignee of the present invention, proposal No. PCB 92077 which was in response to the U.S. Department of Energy Request for Proposal No. EC-77-R-01-5065.
It would be advantageous to provide a means which is adaptable for use with either of the circuit protective devices mentioned above or a combination thereof. It would also be desirable to provide for modular growth, expansion or design as the particular application requires. It is also advantageous to provide a means which is less complex and less expensive to produce.